Enclosed rail stations exceeding annual limits for NO2 in two weeks

Nitrogen Dioxide (NO2) levels in Edinburgh Waverley and London King’s Cross train stations exceeded annual limits in just two weeks, the Rail Safety and Standards Board (RSSB) has reported.

Researchers from Edinburgh University and King’s College London also found that average levels of particulate matter (PM2.5 and PM10) were higher inside the stations than outside them, although they didn’t breach EU limits.

The researchers said the high levels in the two train stations were ‘principally’ due to emissions from diesel trains, but also from other rail-related sources such as rail and wheel wear and other nearby sources such as food outlets.

‘A strong positive association was observed between the number of diesel trains and the concentration of NO2,’ the study said.

‘This was also apparent for PM2.5, but as this pollutant has a range of sources, the correlation was less strong.’

Trains at Edinburgh Waverley station. An RSSB report found that NO2 levels at Edinburgh Waverley exceeded annual limits in just two weeks, largely due to emissions from diesel trains.

They found that inside both stations, concentrations were higher closer to the platforms, especially those with a higher number of diesel services.

The report particularly raised concerns about pollutants at Edinburgh Waverley due to its higher number of diesel trains, noting high concentrations of NO2 and PM2.5 along its main concourse.

However, it compared the quality of air in both Edinburgh Waverley and London King’s Cross as ‘similar to standing close to a heavily trafficked road in a city centre’.

The research raises concerns about the pollution caused by diesel emissions at busy rail stations, which are particularly vulnerable to high concentrations of pollution if they are enclosed under overhead roofs.

Network Rail, who commissioned the study, said that while rail is the ‘greenest’ way of moving people and goods around in large numbers, there is still ‘much more’ the rail industry can do to tackle air pollution.

‘We recognise diesel engine exhaust emissions as an emerging issue at some of our managed stations and have commissioned research to improve our understanding, and inform the actions we are already taking and intend to take in future,’ the spokesperson added.

‘This will help make these station environments more pleasant and safer for our customers and all railway staff.’

Britain’s rail industry remains heavily reliant on fossil fuels, with around 29% of the country’s fleet currently running only on diesel fuel.